Intravascular ultrasound (IVUS) imaging is widely used in interventional cardiology as a diagnostic tool for assessing a vessel, such as an artery, within the human body to determine the need for treatment, to guide intervention, and/or to assess its effectiveness. An IVUS imaging system uses ultrasound echoes to form a cross-sectional image of the vessel of interest. Typically, IVUS imaging uses a transducer on an IVUS catheter that both emits ultrasound signals (waves) and receives the reflected ultrasound signals. The emitted ultrasound signals (often referred to as ultrasound pulses) pass easily through most tissues and blood, but they are partially reflected by discontinuities arising from tissue structures (such as the various layers of the vessel wall), red blood cells, and other features of interest. The IVUS imaging system, which is connected to the IVUS catheter by way of a patient interface module, processes the received ultrasound signals (often referred to as ultrasound echoes) to produce a cross-sectional image of the vessel where the IVUS catheter is located.
IVUS catheters typically employ one or more transducers to transmit ultrasound signals and receive reflected ultrasound signals. However, conventional methods and apparatuses for fabricating transducers may not be optimized. For example, conventional methods and apparatuses do not disclose how to shape a thin polymer film into an ultrasound transducer having concave, lens-like geometries in an automated process.
Therefore, while conventional methods and apparatuses of fabricating transducers are generally adequate for their intended purposes, they have not been entirely satisfactory in every aspect.